title: Particular Mal de Meleda phenotypes in Tunisia and mutations founder effect in the Mediterranean region.
abstract: Mal de Meleda (MDM) is a rare, autosomal recessive form of palmoplantar keratoderma. It is characterized by erythema and hyperkeratosis of the palms and soles that progressively extend to the dorsal surface of the hands and feet. It is caused by mutations in SLURP-1 gene encoding for secreted mammalian Ly-6/uPAR-related protein 1 (SLURP-1). We performed mutational analysis by direct sequencing of SLURP-1 gene in order to identify the genetic defect in three unrelated families (families MDM-12, MDM-13, and MDM-14) variably affected with transgressive palmoplantar keratoderma. A spectrum of clinical presentations with variable features has been observed from the pronounced to the transparent hyperkeratosis. We identified the 82delT frame shift mutation in the SLURP-1 gene in both families MDM-12 and MDM-13 and the missense variation p.Cys99Tyr in family MDM-14. To date, the 82delT variation is the most frequent cause of MDM in the world which is in favour of a recurrent molecular defect. The p.Cys99Tyr variation is only described in Tunisian families making evidence of founder effect mutation of likely Tunisian origin. Our patients presented with very severe to relatively mild phenotypes, including multiple keratolytic pits observed for one patient in the hyperkeratotic area which was not previously reported. The phenotypic variability may reflect the influence of additional factors on disease characteristics. This report further expands the spectrum of clinical phenotypes associated with mutations in SLURP1 in the Mediterranean population.
authors.affiliation: Université de Tunis El Manar, Institut Pasteur de Tunis, Laboratoire de Génomique Biomédicale et Oncogénétique (LR11IPT05), BP74, 13 Place Pasteur, Belvédère, 1002 Tunis, Tunisia.
authors.forename: Mbarka
authors.initials: M
authors.lastname: Bchetnia
authors.forename: Nadia
authors.initials: N
authors.lastname: Laroussi
authors.forename: Monia
authors.initials: M
authors.lastname: Youssef
authors.forename: Cherine
authors.initials: C
authors.lastname: Charfeddine
authors.forename: Ahlem Sabrine
authors.initials: AS
authors.lastname: Ben Brick
authors.forename: Mohamed Samir
authors.initials: MS
authors.lastname: Boubaker
authors.forename: Mourad
authors.initials: M
authors.lastname: Mokni
authors.forename: Sonia
authors.initials: S
authors.lastname: Abdelhak
authors.forename: Jameleddine
authors.initials: J
authors.lastname: Zili
authors.forename: Rym
authors.initials: R
authors.lastname: Benmously
mesh_terms: D000950:Antigens, Ly / Q000235:genetics*; D004252:DNA Mutational Analysis; D018703:Founder Effect; D016368:Frameshift Mutation / Q000235:genetics*; D059014:High-Throughput Nucleotide Sequencing; D006801:Humans; D007645:Keratoderma, Palmoplantar / Q000235:genetics* / Q000473:pathology; D019083:Mediterranean Region; D010375:Pedigree; D010641:Phenotype; D014416:Tunisia; D014568:Urokinase-Type Plasminogen Activator / Q000235:genetics*
chemical_list: D000950:Antigens, Ly; C048963:SLURP1 protein, human; D014568:Urokinase-Type Plasminogen Activator